After downloading the ZIP file, expand the project into a directory of your choice.

Start NetBeans, and select the File -> Open Project menu.From the Open Project dialog box,

Navigate to your chosen directory and open the EarthCubeX project. If you receive a message dialog stating that the jfxrt.jar file can't be found, click the Resolve button and navigate to the rt/lib folder subordinate to where you installed the JavaFX 2.0 SDK.

Also, although JavaFX 2.0 for Mac OS will be released after JavaFX 2.0 for Windows is released, it doesn't seem to be far behind, as this video of EarthCube on an early access version of JavaFX for Mac OS demonstrates.